Severe thunderstorms and poor air quality triggered a first alert for the Philadelphia region on Saturday, July 18, 2026.

The Philadelphia region is under a first alert due to poor air quality and severe thunderstorms. While wildfire smoke is expected to improve by late morning, off-and-on thunderstorms will persist throughout the morning. Strong to severe storms are projected to move in as a line this afternoon, potentially bringing damaging winds, hail, and tornadoes after 3 p.m. These storms are expected to move through Pittsburgh and into the south by evening, which may delay local games and events. Meteorologists have placed the area under an Enhanced Risk for severe weather, indicating a high confidence that numerous storms will be severe. Conditions are expected to calm on Sunday and Monday with sunny skies, though some haze will remain. Air quality is forecast to improve from Friday's levels. A new chance for storms will arrive on Tuesday, followed by a period of lower humidity and dry conditions as temperatures drop below normal. Hazy skies may return by next weekend.

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